Re: [PATCH 0/3] flush delalloc by multi-task

[Liu Bo <bo.li.liu@oracle.com>]

On 10/26/2012 09:56 AM, Miao Xie wrote:
>> I can see the potential improvements brought by flushing inodes this way.
>> > 
>> > But I don't think it makes much sense by making waiting process multi-task,
>> > since even we spread wait order extents into different cpus, they just occpied
>> > the cpu and went on waiting and scheduled then, I mean, the bottleneck is on
>> > what we're waiting for.
> Thanks for your comment, I think only btrfs_run_ordered_operations(root, 0) needn't
> wait for the works, the others must wait.
> 
> The first reason is to avoid changing the semantic of those tree function. The second
> reason is we have to wait for the completion of all works, if not, the file data in
> snapshots may be different with the source suvolumes because the flush may not end
> before the snapshot creation.
> 

Yes, it's right that they must wait for all workers to finish.

But I don't mean that(sorry for my confusing words).

IMO we don't need to let *btrfs_wait_ordered_extents()* run as multi-task.

thanks,
liubo